This study investigated the distribution and growth performance of Bolboschoenus planiculmis under varying estuarine environmental conditions. We aimed to determine the optimal planting methods and environmental conditions with respect to salinity, soil texture, and tidal regimes on its growth performance. Our findings revealed a significant reduction in B. planiculmis coverage, shrinking to 955,393 m2 in 2024, representing only 38.59% of that compared to 2004. The plant’s survival rate exhibited a clear salinity gradient: 0 ppt (89±8.01%)>5 ppt (64±4.56%)>15 ppt (37±4.25%)>30 ppt (0±0.00%). Planting density significantly influenced growth, with 24 tubers m-2 yielding the highest number of plants per tuber (14.67±0.33). A planting depth of 5 cm proved optimal for tuber germination and growth. Soil texture analysis demonstrated that a lower sand content promoted growth, with the highest density observed in soil containing 10% sand (435±6.96 plants m-2). Tidal influence also played an important role, with areas experiencing regular tidal fluctuations fostering the most successful growth. Planting tubers or young plants with attached tubers in these tidal zones led to the highest survival rates and biomass.
This study investigates the role of Junam Reservoir and its surrounding paddy fields as a habitat for migratory birds by considering how different scenarios of habitat loss may affect their populations. It will focus on wintering Anatidae species and take advantage of the population data available for Junam Reservoir and adjacent agricultural fields to analyze habitat-use and dependency patterns. A Bayesian regression model was fitted to estimate the relative dependency at each reservoir and paddy field for each bird species. Network analysis was used to assess the interaction structure and connectivity between habitats and bird species. Furthermore, habitat loss scenarios were simulated in order to predict the outcome of reservoir-paddy field loss on the populations of birds. Among these species, the reservoir loss was much more critical for those highly dependent on reservoirs, such as bean goose, Anser fabalis, and Whooper swan, Cygnus cygnus, but the loss of paddy fields became much more vital for those with higher dependence on paddy fields, such as Baikal teal, Anas formosa. Species that depended on both types of habitats, such as the white-naped crane (Antigone vipio) and the hooded crane (Grus monacha), had additive impacts and suffered the most significant population decline when both reservoirs and paddy fields were lost simultaneously. Network analysis demonstrated that both reservoirs and paddy played equally critical roles in the central nodes of the migratory bird species habitat network and acted as important connectors along migration routes. It is exemplary of the need to develop landscape-level means of maintaining migratory birds and ecosystem stability through the incorporation of ecological connectivity between paddy fields and reservoirs and vice-versa. This stresses integrated management relevant for the entire habitat network rather than single-site focused management, a call for multifaceted conservation efforts, securing of alternative habitats, and restoration of degraded habitats.
This study investigated the annual change and distribution of flora, including endangered species, Korean Red List species, and invasive plants, in the Nakdong River Estuary Ecological Park over a 10-year period (2013~2023). The park was established in 2009 as part of the Four Major Rivers Restoration Project. The investigation identified a total of 704 taxa, comprising 137 families, 401 genera, 631 species, 18 subspecies, 38 varieties, 11 forms, and 6 hybrids. Eulsukdo Ecological Park exhibited the highest plant diversity with 531 taxa, followed by Hwamyeong (404 taxa), Samnak (387 taxa), Daejeo (369 taxa), and Maekdo (356 taxa). The endangered wildlife survey identified three endangered plant species (Class II): Euryale ferox, Brasenia schreberi, and Saururus chinensis. Following the endangered species restoration project, E. ferox has been consistently observed both within the restoration area and the riparian of main channel. The Urbanization Index (UI) was highest in Eulsukdo Ecological Park (24.1%), followed by Hwamyeong (20.0%), Samnak (18.1%), Maekdo (17.8%), and Daejeo Ecological Parks (16.7%). Twelve invasive plants were identified: Sicyos angulatus, Lactuca scariola, Ambrosia trifida, Ambrosia artemisiifolia, Solanum carolinense, Aster pilosus, Hypochaeris radicata, Rumex acetosella, S. altissima, Paspalum disticum, Paspalum distichum var. indutum, and Humulus japonicus. Notably, S. altissima showed a significant decrease in its total distribution area, shrinking from 741,092 m2 in 2021 to 241,396 m2 in 2024. Continuous monitoring and management are necessary to prevent invasive plants, including ecosystem-disturbing species, from forming large colonies and hindering the growth of native plants.
This study employed text mining techniques to analyze the major topics and research trends in plant ecological studies conducted in the Nakdong River basin. A total of 131 research articles published between 1977 and 2023 were collected from domestic and international academic databases. Our analysis revealed that the primary research themes include: wetland plant management and restoration, regional flora investigation, the relationship between aquatic plant communities and water quality, wetland plant community structure and distribution, riparian vegetation, and Phragmites australis (common reed). The majority of these studies were based on short-term field surveys (less than one year in duration; 79.7%), with a focus on regional flora investigation (30.5%), vegetation mapping (21.4%), and plant growth characteristics (17.6%). To ensure the longterm sustainability of the Nakdong River ecosystem, we suggest prioritizing long-term ecological research (LTER) initiatives and incorporating diverse research approaches, such as mesocosm experiments that manipulate key environmental factors. This comprehensive approach to plant ecological research will be crucial for evaluating the stability and resilience of the Nakdong River ecosystem and will ultimately contribute to the development of robust, scientifically informed decision-making processes and management strategies.
This study used text mining to analyze public interest and research trends related to the Nakdong River. We examined news articles (1990~2024) and academic publications (1960~2024) to understand the evolving relationship between societal concerns and scientific research. Main findings reveal growing public interest towards the Nakdong River, with initial focus on pollution related to the industrial development shifting to large-scale river modification projects and water quality issues. This increased awareness mirrored trends in research, where early emphasis on classic ecology and water quality expanded to include sociocultural, educational aspects and advanced methodologies. The study highlights a dynamic interplay between public discourse and scientific inquiry, with research priorities aligning with societal concerns like water pollution, algal blooms, and biodiversity loss, underscoring the need for integrated, multidisciplinary research that addresses emerging environmental challenges and promotes sustainable management of the Nakdong River ecosystem under climate change and other societal shifts.
This study summarizes the history of zooplankton research in the Nakdong River basin, Korea, and discusses its main characteristics by topic. A review of major academic search portals revealed 56 studies on zooplankton in the Nakdong River basin, which account for 27.6% of the 203 domestic freshwater zooplankton studies. With the exception of one study conducted before the construction of the estuary barrage, all other research was carried out after the barrage was built. Of the studies, 27 were related to lotic ecosystems, and 29 focused on lentic ecosystems, with research predominantly conducted south of Daegu Metropolitan City. Short-term studies of less than a year were common for lentic ecosystems, while longterm studies were mainly focused on lotic ecosystems. The key research sites were the Mulgeum water intake in the lower Nakdong River and Upo Wetland, the largest inland wetland in Korea, where research periods and zooplankton sampling were most diverse. Research on predation and prey interactions has been ongoing, as zooplankton plays an intermediary role by feeding on phytoplankton and serving as food for juvenile fish. Recent studies show that, since around 2015, the water quality and zooplankton community dynamics around Mulgeum have changed, requiring continuous monitoring. To address this, predictive model analysis, isotope analysis, and indicator analysis, widely used in Nakdong River research, could help develop health indicators for aquatic ecosystems using zooplankton.
마리나업은 전 세계적으로 고용창출과 경제적 파급효과 측면에서 주요 산업으로 각광받고 있다. 이에 따라 우리나라는 마리나업 육성을 위해 다양한 정책 을 펼치고 있으나 외국적 마리나선박의 국내 유입을 위한 정책은 아직까지 미 흡한 실정이다. 외국적 마리나선박이 우리나라에 입항하기 위해서는 마리나항 만 또는 마리나시설에 입항하여야 하는데, 이러한 마리나항만 및 마리나시설 대부분은 무역항이 아닌 불개항장에 소재하고 있어 외국적 마리나선박의 국내 유입에 있어 장애요소로 작용하고 있다. 외국적 선박이 불개항장에 입항하기 위해서는 불개항장 기항 허가를 통해 기항 목적의 타당성, 선박안전확보 방안, 승선자 무단이탈 관리 방안, 해양오염 예방 방안, 국제협약에 따른 선박검사증 서의 유효성 등과 관련된 엄격한 요건을 만족해야 하기 때문이다. 이에 따라 이와 관련된 법적·제도적 정비가 시급한 실정이다. 이 논문에서는 마리나선박 의 국내 유입 활성화를 통한 우리나라 마리나업 발전을 위해 국내법 규정 완 화, 명확한 기준 확립 및 실효성 있는 안전관리 제도 마련 등 불개항장 기항 허 가 제도 개선방안을 제시한다.
본 연구는 추가적인 장비 없이 UAV만을 사용한 균열폭 측정 및 균열의 3차원 재구성 방법을 제안한다. UAV 사진측량법 및 CNN을이용한 균열의 3차원 재구성 및 균열폭 측정 검증을 위해 5곳의 균열이 존재하는 벽면을 대상으로 균열의 3차원 재구성을 하였 으며 UAV와 균열 사이의 거리 4가지에 대해 균열폭을 측정하고 균열 현미경 측정값과 비교하여 정확성을 검증하였다. 대부분의 균열 에서 균열폭을 정확히 측정하였으나 균열폭이 0.5mm보다 작은 경우와 벽면이 심하게 그늘져 어두운 곳에서는 측정 유효성이 떨어지 는 결과를 보였다.
This study analyzed the relationship between distribution of Bolboschoenus planiculmis which is main food source of swans (national monument species) with environmental factors, discharge, rainfall, and salinity in Eulsuk-do from 2020 to 2023. The distribution area of B. planiculmis in Eulsuk tidal flat was 103,672 m2 in 2020, 95,240 m2 in 2021, 88,163 m2 in 2022, and 110,879 m2 in 2023, and represents a sharp decrease compared to the 400,925 m2 area recorded in 2004. From 2020 to 2023, the growth densities of B. planiculmis were 243.6±12.5 m-2, 135.45±7.38 m-2, 51.10±2.54 m-2, and 238.20±16.36 m-2, respectively, and the biomass was 199.89±28.01 gDW m-2, 18.57±5.12 gDW m-2, 6.55±1.12 gDW m-2, and 153.53±25.43 gDW m-2 in 2020, 2023, 2021, and 2022, respectively. Based on discharge during May~July, which affects plant growth, the left gate discharge of the estuary barrage from 2020 to 2023 was 62,322 m3 sec-1, 33,329 m3 sec-1, 6,810 m3 sec-1, and 93,641 m3 sec-1, respectively; rainfall was 1,136 mm, 799 mm, 297 mm, and 993 mm, respectively; and average salinity was 14.7±9.4 psu, 21.1±4.7 psu, 26.1±2.7 psu, and 14.5± 11.1 psu, respectively. In 2022, cumulative rainfall (978 mm, about 70% of the 30-year average) and discharge (43,226 m3 sec-1) decreased sharply, resulting in the highest mean salinity (25.46 psu), and the distribution area, density, and biomass of the B. planiculmis decreased sharply. In 2023, there was a rise in discharge with an increase in rainfall, leading to a decrease in salinity. Consequently, this environmental change facilitated the recovery of B. planiculmis growth.
This study was conducted to investigate the current status of seagrass species in the Nakdong River estuary from May to June 2023. To survey the seagrass habitat area, the Nakdong River estuary was divided into seven zones. Aerial photography using drones was conducted to find seagrass areas, GPS tracking was carried out on foot in the intertidal zone and by boat and SCUBA diving in the subtidal zone. To analyze the seagrass status, we measured the morphological characteristics, shoot density, and biomass of representative seagrass species in each zone. Four seagrass species were found in this area: Zostera japonica, Z. marina, Ruppia maritima, and Phyllospadix japonicus. The distribution areas of each species was 338.2 ha, 92.9 ha, 0.9 ha, and 1.4 ha, respectively, with a total area of 432.5 ha. Z. japonica was widely distributed in most of the tidal flats and mudflats of the Nakdong River estuary, while Z. marina was restricted to Nulcha-do, Jinu-do, and Dadae-dong. R. maritima occurred within the habitat of Z. japonica in Eulsukdo and Myeongji mudflats, and P. japonicus inhabited rocky areas in Dadae-dong. The shoot density of each species was 4,575.8±338.3 shoots m-2, 244.8±12.0 shoots m-2, 11,302.1±290.0 shoots m-2, and 2862.5±153.5 shoots m-2, respectively. The biomass of each species was 239.7±18.5 gDW m-2, 362.3±20.5 gDW m-2, 33.3±1.2 gDW m-2, and 1,290.0±37.0 gDW m-2, respectively. The results of this study revealed that Z. japonica was dominant in the Nakdong River estuary. In particular, Z. japonica habitats of Eulsukdo, Daema-deung, and Myeongji mudflats were identified as the largest in Korea. The Nakdong River estuary is an important site of ecological, environmental, and economic value, and will require continuous investigation and management of the native seagrasses.
본 연구에서는 무인항공기인 드론을 활용한 VDMS(Vision-based Displacement Measurement System)를 통해 동적변위계측 정 확도와 동특성 추정 신뢰성 검증을 위한 동적실험을 실시하였다. 비행하는 드론의 이동 및 회전진동을 보정하기 위해 영상 내부의 변 위가 발생하지 않는 고정점을 활용한 보정밥법을 사용하였으며, 검증을 위해 설치한 범용 센서인 LVDT와 LDS의 변위계측 결과와 비 교하여 그 오차를 시간영역과 진동수영역에서 분석하였다. 3가지 타입의 장비 모두 최대 변위 도달 및 주기 운동 계측에 있어서 대체 적으로 유사한 결과를 나타내었다. LDS 기준의 오차 분석 결과, 드론과 LVDT는 가진 진동수 변화에 의한 오차 값은 미비하나, 최대 발생 변위가 작을수록 오차 값은 증가하였다.
Bolboschoenus planiculmis has been acknowledged as a key species in whooper swans (Cygnus cygnus) habitat by providing food for this migratory waterfowl. B. planiculmis wetlands are being degraded by water shortages and salinization caused by anthropogenic activities and climate changes. In 2004, the distribution of B. planiculmis in the tidal flats of the Nakdong Estuary was 2,475,568 m2, and in 2021, the distribution area was 798,731 m2, which decreased by 32.3%. In order to restore the degraded B. planiculmis wetlands, shoot transplantation and seed sowing were tentatively used in three places with different salinity and water levels. The average density per unit area in September at the optimal growth period after planting were A (fresh water level 50 cm) 58±15.65 m-2, B (brackish water level 0~5 cm) 188±63.83 m-2, C (brackish water level 0 cm or less) 188±45.13 m-2. The tubers were observed as A 0 g dw m-2, B 25.32±2.94 g dw m-2, and C 13.39±0.91 g dw m-2. Tubers were distributed in the soil, with only 3.0% at the 10~20 cm depth but 97.0% at the 0~10 cm depth. In contrast, the germination rate of B. planiculmis seeds was observed to be 0%. Results of this study provide technical support for the restoration of B. planiculmis wetland and the improvement in the quality of whooper swans habitat.
본 연구는 4차 산업혁명 및 디지털 전환 역량과 관련된 176개의 선행연구를 기반으로 빈도 분석과 네트워크 분석을 통한 메타분석 연구이다. 국내외 기관·학술자료·도서 등의 선행연구로부터 역량을 추출하고 통제 및 범주화 작업을 거쳐 최종 역량을 도출하였으며 이를 학계와 산업계로 나누어 분석하였다. 분석 결과 '의사소통'과 '창의성', '협업 능력'에 대한 역량이 가장 높은 빈도를 보였으며, 학계에서는문제 해결과 문제 발견이 업계에서는 ICT 기술과 융합적 사고력 등이 뒤를 이었다. 또한, 연결 중심성, 매개 중심성, 위세 중심성의 네트워크 분석을 실시하였다. 그 결과 연결 중심성에서는 의사소통과 창의성역량이 학계와 산업계 모두에서 높은 중심성을 보이는 것으로 나타났다. 또한, 위세 중심성 분석 결과 학계에서는 의사소통, 문제 해결, 창의성, 협업 능력, 문제 발견 역량이, 산업계에서는 창의성, 자기주도성, 유연성, 리더십, 문제 해결이 상위 역량으로 도출되었다. 본 연구는 4차 산업혁명 시대에서 요구되는 역량들을 학계와 산업계를 기준으로 그 차이를 확인하고자 하였으며, 역량 간의 관계성을 확인함으로써 추후역량 연구의 방향성과 실천적 함의를 제시하고자 하였다.
Anthropogenic disturbances on freshwater ecosystem are known to degrade biodiversity, especially on fish assemblage. In this study, we have conducted fish surveys to identify impact of a bridge construction on fish assemblages. A total of eight study sites were surveyed in the Danjang and the Dong Stream in southern part of South Korea from June to November in 2021. The fish samplings were carried out five times, using cast-nets (10×10 mm mesh size), scoop-nets (4×4 mm, 5×5 mm mesh size), set-nets (10×10 mm mesh size), and fish traps (3×3 mm mesh size), along with the Stream/River Ecosystem Survey and Health Assessment by the Ministry of Environment of Korea and basic water quality measurement. Also, we applied the species diversity index and length-weight relationship regressions on certain species to identify interspecific growth rate differences in accordance with study sites. As a result, a total of 782 individuals, 23 species and 10 families were collected. The dominant species was Zacco Koreanus and relative abundance was 50.89%. When applying the length-weight relationship regressions on certain species, the ‘b’ value for Z. Koreanus was lower at the downstream points than at the upstream points of the construction site. In addition, when comparing to the results of the past survey, relative density of demersal fish at the upstream and downstream points decreased from 26% to 1.4%, and from 18% to 6.3%, respectively. In conclusion, it is considered that bridge construction negatively affects the habitat of fishes, especially on demersal fishes. Therefore, appropriate conservation efforts such as installation of silt protector and sand sedimentation pond are needed to alleviate the disturbance in habitat such as occurrence of turbidity and destruction of micro-habitats.
The spread of invasive alien plants is one of the most important causes of habitat and biodiversity loss. This research was conducted to secure basic data for the control of the invasive alien plant Solidago altissima. The following research objects were examined: the control; one-time mowing in June (1M6); twotime mowing in June and July (2M6M7); one-time mowing in Jun plus one-time Uprooting in July (2M6U7). The length growth in October, when the growth of S. altissima was completed, was in the order of control (199±19.96 cm), 1M6 (152±13.41 cm), 2M6U7 (54±3.17 cm), and 2M6M7 (45±19.96 cm). The 2M6M7 and 2M6U7 treatment was the most effective at inhibiting S. altissima of density, of 50.8% and 26.2% compared to the control, respectively. In contrast, one-time mowing (1M6) resulted in an increase in density compared to the control by 119.7%. In addition, this treatment also reduced flowering rate (%) of S. altissima. The most effective treatment among those tested was 2M6U7.
본 연구에서는 드론을 활용한 변위계측에서 드론의 회전진동 보정을 위해 드론 내부의 가속도계를 이용하는 방법 대신에 드 론 영상 내부의 변위가 발생하지 않는 고정점을 활용한 드론의 회전진동 보정방법을 제안하고자 한다. 영상 내부의 고정점을 활용한 드론 회전진동 보정을 위한 예비 연구로서, 카메라를 고정시킨 후 타겟을 회전하여 회전각도를 측정하는 실험과 회전하는 카메라를 통 해 변위가 발생하는 모형구조물의 변위를 계측하는 실험을 통해 카메라의 회전진동이 발생하는 경우 변위 계측정확도를 검증하였다. 변위가 3mm 이하로 발생 시 카메라 진동이 발생하였을 때 계측 신뢰도가 낮은 반면, 변위가 3mm를 초과하여 발생한 경우 비교적 정 확하게 계측되었다.
제 4차 산업혁명으로 기업은 내, 외부적인 변화를 마주하고 있다. 변화에 대응하고 생존을 넘어 지속적 인 성장을 위해 기업은 ICT 기술을 도입하고 업무 효율화를 추구하며 구성원의 역량 강화 등의 디지털 트랜스포메이션을 통해 대응하고 있다. 그러나 물적, 인적 자원을 구입하고 조달하는 데 한계가 있는 중소기업은 이러한 변화에 대응하는 데 어려움을 경험한다. 이를 극복하기 위한 대안으로 중소기업 임직원의 ICT 기술 역량 강화의 필요성이 대두되고 있다. 이에 본 연구는 디지털 트렌스포메이션 시대, 중소기업 임직원의 ICT 기술 역량 강화를 위한 교육의 효과성 증진을 목표로 서울 소재 중소기업의 최고경영진이 인식하는 ICT 기술에 대한 산업별 교육 요구도를 조사 및 분석하는 데 연구의 목적을 둔다. 이를 위해 서울산업진흥원에서 진행한 ‘서울기업 디지털 리더십 과정’ 교육 수료자를 대상으로 데이터를 수집하였 다. 수집된 데이터를 기반으로 t 검정, Borich 계수, the Locus for Focus 모델을 통해 요구도를 분석하였 다. 분석 결과 산업별 최우선 순위군에 속한 ICT 기술은 상이한 것으로 나타났다. 또한, 산업별 결과를 종합하면 대다수의 업종에서 우선적으로 고려되어야 할 요인은 인공지능, 가상증강현실로 나타났으며 빅 데이터는 특정 업종에서 우선적으로 고려되어야 할 요인으로 나타났다. 연구 결과를 바탕으로 산업별 ICT 기술 교육에 대한 실천적 방안을 제시하였다.
This study is a plan on the way to strengthen the survival ability by increasing the use time of air respirator by applying emergency breathing method in the situation where firefighter has to wait for RIT (Rapid Intervention Teams) because it is impossible to escape by himself or emergency escape during isolation during field activities. The research procedure first drew problems by conducting a survey on fire fighters under the Seoul Fire and Disaster Headquarters, and conducted an experiment to compare normal breathing and emergency breathing with 20 members of the Seoul 119 Special Rescue Team, and suggested emergency breathing method and training process modeling that can be applied to each field situation based on the data obtained. The experiment was conducted over 9 weeks, and it was divided into three categories: field activity situation, movement (emergency escape assumption) situation, and place (assume waiting for RIT). In the field activity situation experiment, it was confirmed that the application of skip breathing method was appropriate and the use time of air respirator increased about 1.6 ~ 1.9 times. In the moving situation or the in-situ situation, wheel breathing method was appropriate and the use time of air respirator increased about 1.6 ~ 2.4 times. However, when conducting intense activities in the field activity situation, it is recommended to use it limitedly because it is difficult to apply the emergency breathing method. If emergency breathing is not clearly learned in the body, it is difficult to use in the field, so I think systematic and continuous training is necessary. This study suggests that the application of emergency breathing method is effective enough to strengthen the survival ability of firefighters in the field.